Constant velocity universal joint



Nov. 6, 1951 F. w. SAMPSON CONSTANT VELOCITY UNIVERSAL JOINT 2SHEETSSHEET 1 Filed July 17, 1946 INVENTOR. FBCDE18/0K W6AMP8OA/ 5%001/Maw Q M Nov. 6, 1951 2 SHEETS-SHEET 2 Filed July 17, 1946 INVENTOR.FBEqEB/GK M-SAMPSOA/ Patented Nov. #6, 1 951 i"- OFFICE CONSTANTVELOCITY UNIVERSAL JOINT Frederick W. Sampson, Dayton, Ohio, assignor toGeneral Motors Corporation, Detroit, Mich., a corporation of DelawareApplication July 17, 1946, Serial No. 684,318

'5 Claims. (Cl. 64-21) This invention relates to improvements inconstant velocity universal joints for transmitting rotary motion from adrive shaft to a driven shaft at the same angular velocity even tho saidshafts are non-aligned.

One object of this invention is to provide an improved constant velocityuniversal joint having very little sliding friction between itsrelatively movable essential parts which transmit the torque loadbetween the connected shafts.

A particular feature of this invention is the arrangement of theessential parts whereby rolling motion is substituted for sliding motionbetween the relatively movable essential parts which transmit the torqueload.

Another object is to provide such a constant velocity joint having anefiicient rugged structure which lends itself to low-cost manufacture.

Another object is to provide such a joint having a relatively hightorque capacity forthe relatively small outer diameter required for itsessential torque-carrying parts.

Additional advantages of this invention will appear hereinafter from thedetailed description thereof.

In the drawings:

Fig. 1 is a longitudinal section (on line of Fig. 2) thru a joint madeaccording to this invention. The shafts, shaft balls and trunnionrollers are shown in elevation.

Fig. 2 is a longitudinal section on the center line XY of Fig. 1, withthe shaft parts shown in elevation.

Fig. 3 is a longitudinal section similar to Fig. 1 but shows the twoshafts swung out of alignment almost to the maximum angle permitted bythis particular design.

Fig. 4 is a transverse section 4-4 of Fig. 2.

Similar reference characters refer to similar parts thruout thed:awings. v

For the purpose of this description only, shaft I is designated as thedrive shaft and shaft II the driven shaft. A connecting block I 2connects shafts l0 and II and transmits driving torque therebetween ineither direction of rotation. Shafts l0 and H each has an enlargedspherical portion or balls l5 near its inner end which serves as theball for the two ball and socket connections with said block l2. Blockl2 has two spherical bearing areas or seats I 6 (see Figs. 2 and 4)which serve as the'bearing sockets for and positively retain balls I5.Thus shafts l0 and II each has a ball and socket bearing (designated asa whole by 20) upon block I 2. The

taken on line centers 2| of these two ball and socket bearings 20 lie onthe longitudinal axis XY of block l2 and are spaced apart at apredetermined fixed distance.

Shafts l0 and H each has fixed thereto two radially opposed trunnions 25whose axes pass thru the centers 2| of the ball and socket joints 20.Rotatably mounted on each of these trune nions 25 is a conical roller 26whose conicalbearing surface 21 has its apex at the center 2| of itsball l5. Trunnions 25 easily rotate within said conical rollers 26whenever required during operation. Small needle roller bearings may beprovided between said trunnions 25 and the rollers 26 to further reducefriction. The connecting block I2 has in effect annular races 30accurately corresponding in section with the conical rollers 26 and alsocentered at the centers 2| of the two ball and socket joints 20. Theconical rollers 26 have just sufficient clearance within their taperedsection races 30 (see Fig. 4) to cause their conical bearing surfaces 21to roll easily upon races 30 whenever required during operation. Thecentral plane of the two races 30 (indicated by the line P-P in Fig. 4)passes thru the longitudinal axis XY of block I2 and of course also thruthe two centers 2| of the two ball and socket joints 29.

In order to permit ready assembly of the parts and especially tofacilitate machining of interior surfaces of block |2, said block I2 ismade in two separate halves [3 divided along the plane PP which isperpendicular to the paper in Fig. 4. These two halves l3 are boltedrigidly ,together by the two through bolts I4 whose axes extendperpendicular to plane PP and pass thru the centers 2| of the two ballsl5 respectively. Balls l5 have suitable slots I! cut therein to permitshafts I0 and II to swing about centers 2| in a plane perpendicular toplane P-P, that is, in a plane perpendicular to the paper in Fig. 1.When shafts l0 and swing about centers 2| within the plane P-P, that is,in the plane of the paper in Figs. 1 and 3, the balls I 5 will merelypivot about the axes of said bolts H, as shown in Fig. 3. Thus balls I5are permitted a universal swinging movement about their centers 2|regardless of the fact that bolts l4 extend thru said balls and rigidlybolt the two halves 3 of connecting block [2 together. If desired,suitable gaskets 3 may be provided in the long curved grooves cut in thecontacting faces of the two halves |3' of block l2, as clearly shown inFigs. 1 and 3. Such gaskets 3 will aid in very accurately aligning thetwo halves l3 and maintaining ammo always make equal angles with thelongitudinal- XY of connecting block II. Referring to m. 8 which showsshafts II and it out of alignanglesA andBbesubstantially equal at alltimes. The particular means shown in the drawings for maintaining andII, will centers Ii of the two spaced apart at a nxed distance. Shaftthe axially aligned pin it projecting ri its inner end and slidablymounted therethe pilot ball 4.. Shaft II has rigid with end aproiectingsocket member If hava spherical socket 42 which retains pilotball seated therein. The center 43 of spherical 42 is made substantiallyequidistant from two centers 2|. Now when shafts ll andil pivot aboutcenters II (Fig. 3) as they are moved out of alignment, pilot ball willslide axially upon its journal pin II and rotate slightly withints'spherical socket seat 42. This willcause the block if to move to suchposition. that its vertical center line (as viewed in Fig. 3) willsubstantially bisect the angle between the axes of shafts II and II.Orin other words, angle A will always be substantially equal to angle Bwhen shafts ii and ii are moved out of alignment. Let us consider thesmall triangle B01) in Fig. 3. If the distance BC equals the distanceBD, then triangleBCDisisoscelesandhenceangleBCD (whichis same as angleA) must equal angle 300 (which is same as angle B)., It is pointed outthat pilot ball ll coasting with its socket it maintains distances BCand Bl) not precisely equal but substantially so for all angles betweenshafts is and ii for which this universal joint is intended to be used.'Preferably the unvarying distanceBDismadeequaltodistanceBCwhen theangle between shafts II and II is about one half that normallyencountered in the particular installation for which the joint isintended. Then angles will be maintained precisely equal to angle 8 whenthe angle between said shafts is at its approximate average value andapproximately equal thereto for all other angles encountered in use. Inother words, this simple approximation is sufilciently accurate forpractical purposes in most cases. But this invention is not limited tothis particular form of pilot connection shown and described since othersuitable forms of pilot connection between shafts it and l I may bereadily arranged and used with this joint if so desired.

In operation of thh Joint (assuming shaft ll h the drive shaft rotatingat uniform speed) the two conical rollers ll of shaft II will have asubstantial and rug ed bearing contact upon its races 8. on block I!which will efficiently transmit torque to block I! and cause it torotate. Similarly block I! has the same sort of bearingcontectupontheconicalrollersflofshaft II which willtransmittorquetoshaftIi andeauseitto rotate. Whenshafts II and il areinalignment.

block I! will rotate uniformly with the two shafts. when said shafts arenon-aligned (as shown in Fig.8).theangularspeedofblock l2 willvaryandpassthruamaximumandaminimumvalueeveryisodegreesofrotatioaneverthelesstheangularspeedsofthetwosbaftsllandilwill remain substantially uniform andequal. this beingduetothefactthattheaxisL-Yofblock I! always makessubstantially the same angle withtheaxesofthetwoshaftsllandii.asdescribed above. During operation the conical surfaces ll of rollershaveapure rolling motion,toandfroasrequired,upontheirannular.rscesllandremainataconstantradialdissocket J6me 2| lie on said axis x rtance from the centers ll. Rollers is are restrained against movingradially outward from centers it by the engagement of their outertapered surfaces is upon correspondingly shaped.abuttingsurfaeesllontheannularracessflsee Pig. 4). In the form shown inthe drawings. the tapered abutting surfaces fl are near the outer,diameter of said rollers. If so desired. rollers is may be similarlyratrained against moving radially outward by spherical or rounded outerends on said rollers which have a relatively small bearing area againstthe outer cylindricalsurface Ii ofracesll attheaxialcenter of saidrollers. Block I! is provided with suitable conical end openings I toprovide proper clearance for the maximum swing out of alignment ofshaftsI. and ii (seel'ig.3).

Thepartsofthisiointdescribeduptothis point are what may be called theessential structure thereof. In any installation where the joint isenclosed and kept properly lubricated in such enclosure. no furtherhousing for the Joint is necessary or desirable. In installations whereno such outer enclosure is provided. the housing members OI shown in thedrawings are provided. The two housing members or spherical shells Ieach has a central sleeve I which may he slipped endwise over its shaftand retained in place by the coil spring .2, spring cup 08, and springretainer ring as. The metal shell I. may have an outer covering is ofsoft rubber vulcanized thereto wherever such is dedred for protectivepurposes. Thetwo openendsofblock lfareilaredoutand form annular flangesll' whose outer marginal edges Ii are preferably formed to accuratelyconform with the inner spherical surfaces of shells [I when said shellsare properly centered with the centers Ii. Preferably an annularanti-frictionsealring I!issuitablyretainedintbemarginaledgellofthetwoflanges'lltotakethe bearingpressure between shell I and said flange 10. The coil springs I! serveto provide a suitable bearing pressure between the two shells II andseal rings If to effectively seal the lubricant used within the joint.The two shells I. both rotate and swing with their shafts II and ilrespectively, hence the only sliding of seal rings 12 on shells occurswhen shafts II and il move out of alignment.

Thepartsofthisiointmaybereadilyassembled as follows. The four conicalrollers fl are slipped endwise upon their trunnions II on the two shaftsll and ii. the pilot ball ll is properly located within its socket s: onshaft ll. then the two shafts are brought together and the pilot ball 0on shaft II is slipped over the end of its journal pin so. Then thisassembly is set within one open half is of block if so that balls ilseat within their half-sockets it on block If and conical rollers itproperly seat upon the races 8.. Then the other half ll of block is isset over this assembly and the two bolts N inserted thru their holes inblock iI-andtheirslots il inballs ilandtheirnuts applied to very rigidlyclamp the two halves ll of block I: together. The housing shells u, ifused, may be slipped endwise over their respective shafts and be pressedup against their seal rings 12 and then retained in place by the coilsprings 62, spring cups 63, and retainer rings 84 which are retained inplace by suitable grooves 86 in the shafts. A suitable lubricant fillerplug may be provided at any desired location whereby to maintain thejoint filled with lubricant to the desired degree. a

If so desired, other shaped rolling members may be substituted for theconical rollers 26, such for instance as spherical balls, elongatedrollers having an oval-shaped rolling surface, or even cylindricalrollers. In case of any such substitution, the sectional shape of theannular races are changed accordingly so that said races will provide agood rolling surface for said rolling members and a large bearingcontact between said races and rolling members.

' While the embodiment of the present invention as herein disclosed,constitutes a preferred form, it is to be understood that other formsmight be adopted, all coming within the scope of the claims whichfollow.

What is claimed is as follows: i 1. A constant velocity universal jointcomprising: a driving shaft member and a driven shaft member each havingon its connected end portion an axially aligned ball, a connecting blockhaving two spaced spherical sockets for said balls whereby said shaftmembers are con-- nected to said block by two spaced ball and socketjoints, said balls each having opposed radially projecting trunnionswhose axes all swing in the same plane, a conical roller rotatablymounted on each of said trunnions, the apices of said conical rollersbeing at the centers of their respective ball and socket joints, saidblock having corresponding conical cross sectional annular bearing racesfor said conical rollers, the parts being so arranged that torque istransmitted between said shaft members and said block thru 'the mediumof said projecting'trunnions and their rollers, and a pilot jointconnecting the inner ends of said shaft members for causing the axes ofsaid two shaft members to maintain approximately equal angles with thelongitudinal axis of said block when said shaft members move out ofalignment.

2. A constant velocity universal joint comprising: a driving shaftmember and a driven shaft member each having on its connected endportion an axially aligned ball, a connecting block having two spacedspherical sockets for said balls whereby said shaft members areconnected to said block by two spaced ball and socket joints, said ballseach having opposed radially projecting trunnions whose axes all swingin the same plane, a conical roller rotatably mounted on each of saidtrunnions, the apices of said conical rollers being at the centers ofsaid ball and socket joints, said block having annular bearing races forsaid conical rollers, said annular bearing races having conical bearingsurfaces corresponding to the shape of said conical rollers, the partsbeing so arranged that torque is transmitted between said shafts andsaid block thru the medium of said projecting trunnions and theirrollers, the two centers of said annular races being at the centers ofthe two ball and socket joints respectively, and a pilot connectionbetween the adjacent ends of said shaft members for causing the axes ofsaid 6 two shaft members to maintain approximately equal angles with thelongitudinal axis of said block when said shaft members move out ofalignment.

3. A constant velocity universal joint comprising: a driving shaftmember and a driven shaft member each having on its connected endportion an axially aligned ball, a connecting block having two spacedspherical sockets centered on the longitudinal axis of said block forsaid balls whereby said shaft members are each connected to said blockby a ball and socket joint, said balls having radially projectingtrunnions whose axes swing in the same plane, a conical roller rotatablymounted on each trunnion, said connecting block having correspondingconical bearing races upon which said rollers have a substantially purerolling action when said shaft members pivot at said ball and socketjoints about axes other than their trunnion axes. said parts being soarranged that said trunnions pivot within said rollers when said shaftmembers pivot at said ball and socket joints about their trunnion axes,said block serving to transmit torque between said shaft members by theengagement of said rollers with said races, and a pilot connectionbetween adjacent ends of said shaft members for causing the axes of saidtwo shaft members to maintain approximately equal angles with thelongitudinal axis of said block' when said shaft members move out of alinment.

4. A constant velocity universal joint comprising: a driving shaftmember and a driven shaft member each having on its connected endportion an axially aligned ball, a connecting block having two spacedspherical sockets centered on the iongitudinal axis of said block forsaid balls whereby said shaft members are each connected to said blockby a ball and socket joint, said balls having opposed radiallyprojecting trunnions whose axes swing in the same plane, a conicalroller rotatably mounted on each trunnion, said connectingblock havingtwo annular conical section bearing races for said rollers and centeredat the centers of said two ball and socket joints respectively, the

conical rollers of each shaft member having a substantially pure rollingaction upon the corresponding racewhen said shaft members pivot at saidball and socket joints about axes other than their trunnion axes, saidparts being so arranged that said trunnions pivot within said rolle'rswhen said shaft members pivot at said ball and socket joints about theirtrunnion axes, said block serving to transmit torque between said shaftmembers by the engagement of said rollers with said races, and auniversal pilot connection I between the ends of said shaft members forrestraining said shaft members to move together and always maintainapproximately equal angles with the longitudinal axis of said connectingblock.

5. A constant velocity universal joint comprising: a driving shaftmember and a driven shaft member each having on its connected endportion an axially aligned ball, a connecting block having two spacedspherical sockets for said balls whereby said shaft members are eachconnected to said block by ball and socket joints, said balls eachhaving at least one radially projecting trunnion whose axes swing in thesame plane, a substantially cone-shaped roller rotatably mounted on eachtrunnion, said connecting block having two annular bearing racescentered at the centers of said two ball and socket joints respectivelyand upon which said rollers have a substantial amm , 1 rolling actionwhen said shaft members pivot at said ball and socket Joints aboutaxesother than their trunnion axes, said parts being so arranged that saidtrunnions pivot within said rollers when said shaft members pivot atsaid ball and socket joints about their trunnion axes, said blockserving to transmit torque'between said shaft members by the engasement0! said rollers with said raees, and a pilot connection between theadjacent ends of said two shait members for causing the axes of said twoshait members to maintain approximately equal angles with thelongitudinal axis of said block when said shai't members move out ofalignment, said connecting block being made in two halves dividedapproximately atfthe plane within which the axes of said trunnions liewhereby to facilitate assemblina oi said block ,withsaid balls,trunnions and rollers, and means for rigidly said two halves together.

FREDERICK W. SAMPSON. a

ncss arm The following reierenees are oireeord in the file of patent:

UNITED STATIB PATENTS Number Name Date 1,625,410 DeRam Apr. 19. 10273,079,622 1. Rose -4 May 11, 1937 2,106,672 Wollner Jan. 25, 1038 102.1mm 'h'bojevieh Jan. 9, 1940 2,320,903 Horne Sept. 21, 194: IORIIGNPATINTS Number Country Date [5 351,661 I'ranoe ..'O! 1905

